Let's examine the architecture of the opposition to President Trump. Many activist groups have been preparing for a long fight. And this story begins with an epic moment that came the weekend after the president's inauguration. NPR's Sam Sanders reports.

SAM SANDERS, BYLINE: Anna Galland is the executive director of moveon.org's civic action. MoveOn began as an anti-war group during the George W. Bush era. Now the group is focused on fighting Trump.

ANNA GALLAND: The day after the Women's March in Washington, we held a national conference call.

SANDERS: Galland says that conference call was big.

GALLAND: We had 60,000 people join one conference call. The Guinness Book of World Records told us that we broke the record for the world's largest conference call.

SANDERS: Sixty-thousand people on one conference call, that sounds like the conference call from hell.

GALLAND: (Laughter) People stayed the whole time, too.

SANDERS: There are so many other examples. 350.org, a climate action group, they told me the month after the election, they saw donations almost triple. Planned Parenthood says they've got over 600,000 new donors. And the ACLU has raised $80 million since the election. I asked Anthony Romero just how all that money is going to get spent. He's the executive director of the ACLU.

ANTHONY ROMERO: First, the most important thing is we're going to build out our state infrastructure. So we've identified certain key important states with large populations, battleground states where our issues are at play.

SANDERS: Romero says more than half the money will go there. Another $13 million will go to mobilize volunteers. After that, money will go to hiring a bunch of new lawyers at the national level and building new office space for them. Sandra Miniutti is with charitynavigator.org, a watchdog group that rates charities and nonprofits. She has a name for all of this new money groups like the ACLU are receiving - rage giving.

SANDRA MINIUTTI: Yeah. Rage giving is something that's sort of become a new term that's popped up since the election. So people who may not like President Trump's policies then are making donations to contradict those policies.

SANDERS: David Van Slyke is the dean of the Maxwell School of Public Affairs at Syracuse University. And he says the challenge with this new rage giving is keeping it going.

DAVID VAN SLYKE: And what I mean by that is the organization runs the risk of new donors becoming just one-time donors.

SANDERS: And for Van Slyke, a lot of that depends on how these groups meet and set donor expectations.

VAN SLYKE: What is it that you're resisting about the president? Is it the president himself? Is it a particular executive order, a particular appointment?

SANDERS: Michael Cornfield teaches political management at George Washington University. And he says this resistance can take a lesson or two from a protest movement just a few years old - the Tea Party.

MICHAEL CORNFIELD: One of the unusual features - and I think a key to their success - of the Tea Party is that there was no head of the Tea Party.

SANDERS: Cornfield also says the Tea Party succeeded by focusing locally and trying to obstruct every chance they could. Ezra Levin is one of the founders of Indivisible. Indivisible published an online guide on how to effectively lobby Congress and disrupt congressional town halls Tea Party-style. Levin spoke to me on Skype. He said Indivisible began as just a Google Doc. And then the doc crashed, so they built a website. And then the website became something more.

EZRA LEVIN: We explicitly said - you can go back to it - we said, we are not professional organizers. We are not starting an organization. And then, we started an organization.

SANDERS: Indivisible is now officially a 501(c)(4) nonprofit with a website and a donate button. But Ezra Levin admits Indivisible is still figuring things out.

LEVIN: Yeah. So we're definitely building the plane while we fly it.

SANDERS: Building the plane while they fly it. Well, wherever it goes, it may very well be a very big plane. Sam Sanders, NPR News.